Regulator



July 23, 1946. 1.. H. VON QHLSEN REGULATOR Filed Oct.

3 Shams-Sheet l WVENTQW 171011125 July 23, 1946. L. H. VON OHLSEN 2,404,574

REGULATOR Filed Oct. 28, 1942 l 3 Sheets-Sheet 2 Laiuls 11'. V522 0/1156)? $5 -$24, mar/k I I ATTORNEY July 23, 1946.

L. H. VON OHLSEN REGULATOR 3 Sheets-Sheet 3 Filed Oct. 28, 1942 INVENTEJR Louis If. Vbn OhZsen B M ffigmzgy I Patented July 23, 1946 REGULATOR 7 Louis H. Von Ohlsen, New Haven, Conn, assignor to The Safety Car Heating and Lighting Company, Inc., a corporation of Delaware Application October 28, 1942, Serial No. 463,645

7 Claims. (01. 201-51) This invention relates to electrical apparatus, and more in particular to the construction and operation of electrical equipment such, for example, as an electric regulator in a power system.

An object of this invention is to provide an electric regulator which is sturdy in construction and reliable in operation and which is light in weight and inexpensive to manufacture. A further object is to provide an electro-magnetic construction which is economical to manufacture, eflicient and dependable in operation, and adaptable to various conditions which arise. A still further object is to provide apparatus of the above character wherein eflicient use is made of all of the materials of which the apparatus is constructed and wherein all of the various individual mechanical assemblies are of uniformly high efflciency and are durable. A further object is to provide apparatus of the above character wherein a standardized construction can be utilized under a variety of different conditions of operation. A further object is to provide such apparatus which is easily adjustable, and which will remain in adjustment without constant attention. These and other objects will be in part obvious, and in part pointed out below.

The invention accordingly consists in the features of construction, combinations of elements, and arrangements of parts as will be exemplified in the structure to :be hereinafter described, and the scope of the application of which will be indicated in the following claims.

In the drawings:

Figure 1 is a front elevation of an electric regulartor constituting one embodiment of the invention;

Figure 2 is a sectional View of certain of the apparatus shown in Figure 1 and is along the line 2-2 of Figure 3;

Figure 3 is a side elevation from the right of Figure 1;

Figure 4 is a top plan view Figure 5 is a showing of the stampings which are used to construct the magnetic parts of the apparatus;

Figure 6 is a sectional view of the assembled electromagnet construction; and,

Figure 7 is a view of the electro-magnet and armature construction with certain parts broken away.

In the illustrative embodiment of this invention, an electric regulator is provided which includes; a carbon pile the electrical resistance of which is varied in order to obtain the control efiect, illustratively shown herein with the resist- .ance increasing as the pressure on the carbon pile is decreased; an electro-magnet assembly having a rocking armature which is rocked from its initial position due to the effect of the magnetic field to increase the resistance of the carbcn pile; a dashpot assembly to cushion the rocking operation and limit the speed at which the resistance is changed; a compensating spring assembly the efiect of which varies as the spring is extended and which opposes the action of the magnetic field in rocking the armature; a thermoresponsive unit in the form of a bi-metallic strip which varies the tension of the compensating spring assembly in accordance with the ambient temperature; and a carbon pile compression adjustment means which maintains a substantially constant compressing force upon the carbon pile until there is a predetermined movement of the armature from its initial position whereupon the compressive adjustment means is rendered ineffective, and further movement of the armature effects a change in the resistance of the carbon pile.

Referring particularly to Figure 2 of the drawings, the regulator is attached to a panel 2 through two legs 4 and two legs 5 (see Figure 4) by screws 6, (Figure 2) one of which is threaded into each leg With its head countersunk in the panel. Legs 4 are integral with the left-hand vertical arm 8 of a frame construction 9 having a general Ushaped configuration and including a bottom transverse web It) and a right-hand vertical arm l2. Legs 5 (Figure 4) are integral with an angle bracket 1 which is parallel to transverse web ll) of frame 9 and is rigidly held thereto in a manner explained more fully lbelow. Bracket i has a vertical portion extending between the two legs 5 and a horizontal portion which is enlarged and apertured at its center. Rigidly secured in this aperture is a ball-bearing unit l5. Web ID (Figure 2) is similarly enlarged and apertured and. carries a similar ball-bearing unit [3. These two ball-bearing units provide a rockable mounting for a crank shaft l4 and rigidly mounted upon shaft [4 between the ball-bearing units is an armature H; which is pressed onto the shaft.

Crank shaft M also has rigidly mounted upon it a crank assembly shown at the bottom of Figure 1 and designated generally at l8. Crank as- .sembly I8 includes adashpot arm 29 extending to the right and connected to the piston rod 22 of a dashpot 25. Dashpot 25 has a graphite piston 24 connected to the piston rod, and a cylinder 26 rigidly mounted at its upper end on shelf bracket 36 extending from the vertical arm l2 of frame $3. This mounting is provided by a stud 23 integral with the top of the cylinder and extending through the bracket and is clamped thereto by nut The damping effect of dashpot 25 is regulated by adjusting a screw 34 (Figure 2) which controls the air outlet from cylinder 25.

The carbon pile, the resistance of which is varied in order to exert the control effect, extends vertically at the center of Figure l and is designated At the top of carbon pile 3B is a contactor 3'11, above which is an insulator 38 and an anvil is pivotally suspended by a pin 42 from a pile lever l i. At the bottom of carbon pile 33 is a similar arrangement in the form of a contactor 3%, an insulating member El, and an anvil 53 pivotally carried by a pile pin 45 mounted eccentrically on the crank assembly is and secured by a nut 51'. Referring again to the top of the carbon pile assembly, pile lever M is pivoted at its left end on a pin 43 carried by a bracket 46 integral with arm 8 of frame 9. At the right, pile lever M! has a slot Q into which is hooked the upper end of a tension pile spring 56. An adjusting screw 53 is threaded through the lever and is locked in adjusted position by a lock nut 52. The lower end of adjusting screw 59 is positioned above and adapted to engage the top of a sto pin 53 which has an enlarged lower end 59 threaded through a bracket 6i! and locked in adjusted position by a lock nut 62. The threadin on the enlarged portion 59 of stop pin 58 extends above the lock nut 52 and provides an anchor portion 63 upon which is threaded the tightly coiled small diameter lower end of the pile spring 56. This stop pin and pile spring assembly provides a tension control adjustment which acts through pile lever 3 to maintain an initial predetermined pressure on the carbon pile all in a manner to be more fully discussed below.

Crank assembly is is provided at the left with a segment portion 76 which has a hole 16 therein, in which is hooked the lower end of a tension spring it. The upper end of tension spring 78 is coiled tightly and threaded onto the lower end of a threaded anchor pin as. The predetermined adjustment of spring '58 on anchor pin 89 is maintained by a pair of lock nuts 82 and $4. As shown best in Figure 2, anchor pin 80 extends upwardly through an enlarged opening 66 in the horizontal portion 'of bracket 46, and, at the upper end, pin 86 carries a nut 99 which holds a knife-edged washer 83 in adjusted position. The knife-edged portion'iie of washer 88 rests in a groove 92 in the free end of an arched lei-metallic strip '94 which has a hole therethrough, through which pin 80 extends.

Bi-metallic strip 54 is rigidly mounted at its righ -hand end by a pair of screws 96 (see also Figure 4) which are threaded into a horizontal bracket portion 93 (Figure 2) of the frame 9, and which hold a locking plate I06 tightly against the 'top'of the bi-metallic strip. Bracket portion 93, -strip M, and plate IQ!) are recessed between screws to allow for the adjustment of screw 33. Bi-m'etallic strip 94 is curved as shown best in'Fi'gure 2 with a main arch portion and a smaller invertedarch portion, and (see Figure 4) it 'is tapered from its fixed end toward its freeend. This lei-metallic strip is effective to move anchor pin 8?? up and down with changes in ambient tem perature to thus change the tension on tension spring is and maintain the operating characteristics of the regulator constant.

As indicated above, armature Iii is rocked by the action of a magnetic field which opposes the action of sprin '53. This magnetic field is produced by an electro-magnet I32 rigidly mounted (see Figure 2) upon the tWo arms 8 and 12 of the frame 9, and best shown in Figures 6 and '7. This electro-magnet is provided with a solenoid Hi3 and a core res, which has a left-hand pole piece I and a right-hand pole piece 506 (see Figure 7). Pole pieces 435 and H36 have cylindrical pole faces with the same axis as the shaft it about which armature it rocks. Armature I5 is provided with pole tips iii? and we, and the pole faces are cylindri'cal and concentric with the pole faces of pole pieces 5% and Hit. Thus, the air gaps at the two ends of the armature are small and are of uniform length throughout the entire swinging movement of a mature it. However, many of the advantages of this invention can be realized when eccentric pole pieces are used, thus givin air gaps which are not uniform throughout.

Core ice is built up of a plurality of similar laminations of the shape shown in Figure 5 at l 88. Each lamination has therein four holes Iii? which, when the laminations are stacked to form the core, are in alignment (see Figure 6), and the core is held together by sleeves H2 eX- tending through those holes with a pair of ferrules I i held upon the flanged ends of each sleeve. The outwardly extending end faces i it of the four ferrules on each side of the core are ground after assembly to a single plane, and the spacing between the two planes on th opposite sides of the core is accurately controlled to a specified dimension. These two planes are normal to the axis of sleeves H2, and have a predetermined relation ship with respect to pole pieces 35 and I85. Sleeves M2 and ferrules H4 are used to mount the core on the frame 53 with a stud 1 E8 extending through each sleeve and secured to a hole in frame The central portion of each stud is of reduced diameter to provide a clearance 28 about the stud at the center of sleeve I I2 and a tight fit at the two ends of the sleeve. Referring again tov Figure 2, the ends of the four studs 5 it are held in the mounting holes in the two side arms of rame e by nuts l22 (see also Figure 3), and the other ends of the studs are held by similar nuts I24. The lower stud in the frame arms and the upper stud adjacent panel 2 extend through eyes in bracket '8 (Figure 4) which, as indicated above, carries the ball-bearing unit it and thus helps support the crank shaft. These studs iii? and their nuts I22 and I24 thus hold bracket '5 tightly against the end faces H3 on the core, and also press the opposite end faces H3 tightly agains them'achined surfaces of fram 9. Thus, the core Hi4 and bracket 1 are accurately and rigidly secured to frame 9. In this way, core is acts as a spacing and aligning means, and armature i5 is accurately held in place and in alignment with respect to the pole faces of pole pieces Hi5 and H36.

As indicated above, crank assembly l3 and armature it are biased clockwise (Figure 2) by a spring it toward the initial position shown wherein lever 25* of the crank assembly engages the top of an adjustingscrew I23. Screw I28 is threaded through a bracket I33 integral with frame '9 and is held in adjustment by a lock nut I32. The counterclockwise movement of lever ZQ/and thus of armature l 6, is limited by the engagement of the lever with bracket Durtween the full line and broken line positions shown in Figure '7 wherein'the moment of the force exerted by spring I8 in one direction balances the opposed moment of the force exerted by the electro-magnet.

As shown best in Figure 1 in this embodiment, the lower end of spring I8 is hooked in hole I6 in the crank assembly below the radius line perpendicular to the spring, and as the crank assembly swings counterclockwise, hole I6, and thus the lower end of the spring, moves to the right with a resulting shortening of the effective lever arm through which spring 18 acts. This shorten-- ing of the effective lever arm is such as to cause the moment of the force exerted by spring I8 to have the proper value at all times to permit the use of a constant air gap. Under some circumstances, it may be desirable to provide a variable air gap and an increasing efiective lever arm through which the spring acts. Under these circumstances, a hole such as I6 is provided near the top of the cam portion 14 of the crank assembly, and a shortened spring I8 is hooked therein.

Referring to Figure l, the center of pile pin 45 is directly above the center of shaft I4 so that the counterclockwise movement of the crank assembly swings anvil 43 to the left and downwardly. In the initial position of the elements, spring 56 maintains a constant compressive force on carbon pile 36, and the carbon pile holds anvil 40 and lever 44 elevated as shown so that the lower end of adjusting screw 50 is spaced from the top of stop pin 58. Thus, during the initial movement of the crank assembly and anvil 43, the entire carbon pile and anvil 40 move with anvil 43 with spring 56 exerting a follow-up force downwardly through lever 44 with the result that the carbon pile remains compressed. However, after a predetermined swinging movement of lever 44, adjusting screw 50 engages the top of stop pin 50, and this prevents further downward or followup movement of lever 44 and anvil 40. As a result, the further movement of anvil 43 by the counter-clockwise swinging of crank assembly I8, increases the distance between anvils 43 and 40, with a corresponding decrease in the compressive force exerted on the carbon pile. This causes the electrical resistance of the carbon pile to increase in the manner referred to above.

When the armature starts to swing from the full line initial position of Figure '7, the path of the flux is from the extreme tip of pole piece I06 through the armature and to the upper portion of pole piece I05. As the flux increases and the armature swings counterclockwise, the major portion of the flux still passes through the lower portion of pole piece I06, whereas the flux passes only through the upper portion of pole piece I05. Accordingly, pole piece I06 is larger than pole piece I05, and the entire core carries the flux efliciently at all times.

During manufacture, the laminations I08 of core I04 are stacked and fastened together by sleeves H2 and ferrules H4, in the manner discussed above, and solenoid I03 is wound directly onto this core. This type of winding is possible because the pole pieces I05 and I06 are spaced apart so that the cross member of the core which connects the two arms is open in a radial direction. Thus, the core is mounted to rotate about the center of its cross member with suitable insulating material in place, and the core is then rotated and the wire is wound to form the solenoid.

Armature I6 is built up of individual laminations I48 in the same manner as is core I04, and

these laminations are tightly pressed onto shaft I4. Referring to Figure 5, laminations I08 and I48 are stamped from a sheet of iron in a single operation. Theiron from which these laminations are stamped has directional characteristics in the sense that the magnetic characteristics along the sheet of iron are superior in the direction of the grain of the iron, thatis, in the direction in which the sheet was rolled during manufacture. The sheet of iron illustrated was rolled in the direction from top to bottom so that the grain and the superior magnetic characteristics are between the top edge and the lower edge, Accordingly, the laminations I08 and I48 are stamped as shown, and laminations I48 and the two arms of lamination I08 have superior magnetic characteristics in the direction in which the lines of magnetic flux are set up, that is, along their longitudinal dimensions. Referring to Figure 7, armature I6 and the arms of core I04 have these superior characteristics so that the flux lines which are set up by solenoid I03 extend from the ends of the solenoid straight down the two arms of the core and thence across the armature, and all of this path is with the grain of the iron. The only portion of the magnetic circuit which does not have the superior magnetic characteristics is the connecting portion of core I04 which is surrounded by and under the direct influ ence of solenoid I03, the source of the magnetic flux. Thus, eflicient use is made of the iron.

An additional feature aiding in providing an eilicient unit is the provision of the core I04, built up of the U-shaped laminations I08, combined with the provision of minimum air gaps between core I04 and armature I6. Thus, the magnetic structure has no air gaps in its stationary parts and the two gaps between pole pieces I05 and I06 and armature I6 are only large enough for mechanical clearance during movement of the armature. The variable balancing feature and the adjusting and control features of the regulator make it possible to provide this magnetic structure without sacrificing the efiiciency and reliability of the action.

The electrical connections to the regulator are provided, as shown best in Figure 3, through four terminals I33, I34, I40, and I46 mounted on panel 2 with a pair of leads I3I and I32 connecting solenoid I02 to terminals I34 and I33, and with a pair of leads I38 and I44 connecting connector plates 31 and 39 to terminal plates I40 and I46, respectively. In practice, solenoid I02 carries a current which varies in accordance with the control efiect to be exerted, and the current through the carbon pile is then varied by the regulator with the result that the proper control effect is exerted at all times.

The pile spring 56 (Figure 1) maintains constant pressure upon the carbon pile except when this pressure is relieved by the engaging of adjusting screw 50 with stop pin 58. Thus, even though the length of the carbon pile changes dur ing use, the spring 56 maintains constant pressure on the carbon pile. Adjusting screw 50 is readily changed to vary the amount of initial movement of the armature during which no control effect is exerted. The changes in ambient temperature are corrected for by the bi-metallic anchorfpin is increased, the number of turns active as a spring is correspondingly decreased.

As many possible embodiments may be made of theabove invention and as many changes might be made in the embodiment above set forth, it is to be understood that all matter hereinbefore set forth, or shown in the accompanying drawings, is to be interpreted as illustrative and not in a limiting sense.

I claim:

1. In a carbon-pile regulator, the combination of, a U-shaped frame constituting a rigid mounting means and having two leg portions connected together at their lower ends by a base portion and having their free ends extending upwardly, an inverted U-shaped magnetic core having two legs extending along and rigidly clamped to the respective leg portions of said frame with the lower free ends of the legs substantially at the base of the frame and with the base portion of the core being positioned along the side of the leg portions of the frame, a bi-metallic strip extending across the top of said frame with one end rigidly attached to the top of one of said leg portions, a tension spring assembly suspended from the other end of said strip and extending downwardly toward the base portion of said frame, a rotor assembly mounted at the base portion of said frame and adapted to be turned by variations in the magnetic field of said core to exert a motive force which varies in accordance with the control effoot to be exerted, a carbon-pile assembly carried by said frame and positioned longitudinally thereof with its lower end adapted to be moved upwardly to compress the carbon pile in accordance with the control effect desired, and means connecting said tension spring assembly to oppose the action of said motor assembly.

2. Apparatus as described in claim 1 wherein. a dashpot is mounted on the side of said frame opposite said tension spring assembly and is connected to oppose rapid changes in the control effect.

3. Apparatus as described in claim 1 wherein the upper end of said carbon pile is held against a lever which is pivotally carried by one leg of said frame and which is biased against said carbon pile by a coil spring with adjustable stop means limiting the movement of said lever toward said carbon pile, said stop means including a stop rod which is rigidly carried by said frame. and said spring being coiled about and anchored to said rod.

4. Apparatus as described in claim 1 wherein said motor assembly is formed by an electromagnet which rocks an armature with the magnetic parts of the electro-magnet being formed by a plurality of substantially identical laminations of iron in face to face relationship with each lamination forming a complete magnetic path from one end of said armature to the other end thereof.

5. In a carbon pile regulator, a carbon pile assembly, a base construction including means to hold said carbon pile assembly, adjustable biasing means to exert on said carbon pile assembly a predetermined compressive effect and including stop means to limit the action of said biasing means, said biasing means cOmprising a coil spring and said stop means including a rigid longitudinal member extending through the center of said coil spring and having the fixed end of said coil spring attached to said longitudinal member.

6. In a carbon pile regulator, the combination of, a U-shaped frame construction having a pair of substantially parallel spaced longitudinal portions rigidly connected at the base of the U by a base portion, a substantially U-shaped electromagnet rigidly mounted on said frame construction and having a pair of substantially parallel spaced longitudinal portions rigidly connected by a base portion, said electro-magnet being mounted on the frame construction with the respective longitudinal portions in side-by-side parallel relationship and with the base portions oppositely positioned with respect to each other whereby the free ends of the longitudinal por-- tions of the electro-magnet are positioned at the base portion of the frame construction and hav ing substantially cylindrical pole faces, a frame member of substantially the length of the base portion of said frame construction and positioned parallel to said base portion on the opposite side of said electro-magnet, means clamping said frame member to said frame construction whereby said electromagnet is clamped in place and acts as a spacing means to hold said frame member in spaced relationship, a pair of ballbearing units respectively mounted on said frame member and the base portion of said frame construction with their axes in alignment on the axis of said cylindrical pole faces, an armature assembly having an armature positioned between said pole faces and havin armature pole faces substantially concentric with said cylindrical pole faces and having shaft portions respectively extending through said ball-bearing units to provide a rocking support, a tension spring extending longitudinally of said frame construction with one end adjustably secured to the end of said frame construction opposite the base portion thereof and with the other end of said tension spring being attached to said armature assembly at a point beyond the rocking axis whereby a rocking movement of the armature assembly results in a reduction in the length of the lever arm through which the spring acts with the reduction being of sufficient amount to compensate for the increased pull of the extended spring, a rigid elongated stop member positioned substantially parallel to said longitudinal portions of the frame construction, and a coil spring freely coiled around said stop member with the coil spring fixed at one end of the stop member and attached at the other end to means mounted on said frame construction.

'7. Apparatus as described in claim 6 which includes, a carbon pile assembly mounted on said frame construction and including a carbon pile which is positioned substantially parallel to and equidistant from said longitudinal portions of the frame construction, and means to change the compressive action on said carbon pile in accordance with the movement of said armature.

LOUIS H. VON OHLSEN. 

